// Copyright (c) 2020, NVIDIA CORPORATION. All rights reserved.
//
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//
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// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
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#pragma once

#include <condition_variable>
#include <deque>
#include <mutex>

namespace triton { namespace common {

//
// C++11 doesn't have a sync queue so we implement a simple one.
//
template <typename Item>
class SyncQueue {
 public:
  SyncQueue() {}

  bool Empty()
  {
    std::lock_guard<std::mutex> lk(mu_);
    return queue_.empty();
  }

  Item Get()
  {
    std::unique_lock<std::mutex> lk(mu_);
    if (queue_.empty()) {
      cv_.wait(lk, [this] { return !queue_.empty(); });
    }
    auto res = std::move(queue_.front());
    queue_.pop_front();
    return res;
  }

  void Put(const Item& value)
  {
    {
      std::lock_guard<std::mutex> lk(mu_);
      queue_.push_back(value);
    }
    cv_.notify_all();
  }

  void Put(Item&& value)
  {
    {
      std::lock_guard<std::mutex> lk(mu_);
      queue_.push_back(std::move(value));
    }
    cv_.notify_all();
  }

 private:
  std::mutex mu_;
  std::condition_variable cv_;
  std::deque<Item> queue_;
};

}}  // namespace triton::common